The greatest number of 6 digits is 999999.
The greatest number must be divisible by L.C.M. of 24, 15 and 36
24 = 23 x 3
15 = 3 x 5
36 = 2 x 3
L.C.M = 2 x 3 x 5
= 360
To find the greatest number 999999 must be subtracted by the remainder when 999999 is divided by 360
The greatest number in 6 digits = 999999 – 279 = 999720
